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Re: C Containers Library vs STL

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On 08/ 4/11 07:02 PM, Juha Nieminen wrote:
> Ian Collins<ian-news@hotmail.com>  wrote:
>> the run time drops to 0.66 seconds.
>
>    If you wanted to reduce the running time even further, and assuming the
> entire input file fits in RAM, what you could do is to read the entire
> file into RAM with one single fread() call and then use a std::set of
> char* (and the proper comparator), each pointer pointing to this single
> data block (which needs newlines replaced with null characters).

Running more than once should be sufficient to cache the file in RAM.

>    In this case the (probably significant) speedup comes from removing the
> need to make a memory allocation for each line.

My point was the choice of container was the dominant player in this 
comparison.  All of the above optimisations can be applied to either 
version.

-- 
Ian Collins

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Thread

C Containers Library vs STL jacob navia <jacob@spamsink.net> - 2011-08-03 22:40 +0200
  Re: C Containers Library vs STL Ian Collins <ian-news@hotmail.com> - 2011-08-04 09:13 +1200
    Re: C Containers Library vs STL Robert Wessel <robertwessel2@yahoo.com> - 2011-08-03 17:36 -0500
      Re: C Containers Library vs STL Robert Wessel <robertwessel2@yahoo.com> - 2011-08-03 17:38 -0500
        Re: C Containers Library vs STL jacob navia <jacob@spamsink.net> - 2011-08-04 01:30 +0200
          Re: C Containers Library vs STL Robert Wessel <robertwessel2@yahoo.com> - 2011-08-03 18:40 -0500
            Re: C Containers Library vs STL jacob navia <jacob@spamsink.net> - 2011-08-04 13:42 +0200
          Re: C Containers Library vs STL Ian Collins <ian-news@hotmail.com> - 2011-08-04 12:34 +1200
            Re: C Containers Library vs STL Ian Collins <ian-news@hotmail.com> - 2011-08-04 13:38 +1200
              Re: C Containers Library vs STL Juha Nieminen <nospam@thanks.invalid> - 2011-08-04 07:02 +0000
                Re: C Containers Library vs STL Ian Collins <ian-news@hotmail.com> - 2011-08-04 19:40 +1200
                Re: C Containers Library vs STL Juha Nieminen <nospam@thanks.invalid> - 2011-08-04 14:16 +0000
                Re: C Containers Library vs STL jacob navia <jacob@spamsink.net> - 2011-08-04 16:25 +0200
                Re: C Containers Library vs STL Nobody <nobody@nowhere.com> - 2011-08-04 21:40 +0100
            Re: C Containers Library vs STL jacob navia <jacob@spamsink.net> - 2011-08-04 09:42 +0200
              Re: C Containers Library vs STL Ian Collins <ian-news@hotmail.com> - 2011-08-04 19:59 +1200
              Re: C Containers Library vs STL Marc <marc.glisse@gmail.com> - 2011-08-04 12:47 +0000
                Re: C Containers Library vs STL jacob navia <jacob@spamsink.net> - 2011-08-04 15:17 +0200

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